Franka ROS Interface version for franka-ros v0.7.1-release

A ROS/Python API for controlling and managing the Franka Emika Panda robot (real and simulated). Contains exposed controllers for the robot (joint position, velocity, torque), interfaces for the gripper, controller manager, coordinate frames interface, etc. Provides almost complete sim-to-real / real-to-sim transfer of code.

Version corresponding to franka_ros release version 0.7.1.

Franka ROS Interface version for franka-ros v0.6.0-release

fix travis config